give me toothaches just from kissin' me
by black-ostias
Summary: the original plan had been to greet mob at the train station, embrace him, whisper that you had a plug up your ass, then enjoy watching him squirm. but you'd severely overestimated his patience and resolve. / in which reigen both loses and wins, in the end, as he always does.


**a gift for a friend.**

* * *

Your throat is literally getting crushed by the urge to shout, even with a hand over your mouth as you try to brace yourself against the cold tile at your side. Mob tugs on the plug inside you again, slower this time, deliberate, and you almost bang your forehead against the door.

"Mob," you try to hiss between your teeth, but it's not a rebuke so much as a little-dog whine. "C'mon, let's go already, I told you this was your present for _later_—"

But your partner doesn't seem to hear you. "I can't believe you actually got one. Where'd you even get this idea?" His tone would seem almost conversational to someone who doesn't know him well. The tremor winding through it, plus the hard-on against your hip, gives him away.

"I'll answer your questions later, all you wa_ahnt_—" He traces a finger around the tender stretch of your hole around the plug, and more of your logic sputters and dies.

The original plan had been to greet Mob at the train station, embrace him, whisper that you had a plug up your ass so he wouldn't have to worry about fucking you that night, then enjoy his twenty-fifth birthday party watching him squirm. But you'd severely overestimated his patience and resolve, since his eyes flashed, suddenly made of steel, and he just dragged you to the nearest single-stall bathroom and pulled down your pants without so much as a by-your-leave.

You thought you could talk him out of it, but you should've known it's impossible to get Mob to reconsider a decision he's made. Now you don't want to talk yourself out of this either. You can't. You're so turned on even the tips of your hair feel like they're going to catch fire.

Mob's hand slides up your back, broad palm bumping on the ratchets of your spine. He grasps the plug by its base, his fingernails grazing your ass cheeks making you shudder, then starts taking it out. The slow, sweet stretch and ache becomes sharp desperation when your hole catches against the widest part of the plug. When it slips out at last you can't help clenching and missing the intrusion, feeling empty and gaping. You whimper loud enough that Mob groans and bites your shoulder through your shirt. "Arataka, I'm gonna fuck you now," he rasps into your ear. Not asking, simply declaring, as imminent as the changing of seasons. You're too delirious to care, no longer daunted by the dull roar of the world outside.

"_Please_."

Mob doesn't bother with a condom, which doesn't matter since you're both clean. You do worry about the mess that'll be made as the head of his cock presses against for precisely half a second. And then he sinks in without preamble and your brain halts altogether.

He thrusts slow at first, finding an angle in this standing position while in such a cramped space. His hand warmly sweeping over and smoothing down your chest, frees you from your boxers. The absurdity of the situations hits you: you're both still mostly clothed and yet his dick is up your ass. While you're in a train station. You'd laugh except you're trying not to sob instead, eyes squeezed shut as the thickness of him wrecks your walls.

You let your head fall against Mob's shoulder as he grows more confident. His arm coils like a snake around your chest, bracing as he thrusts a little harder, and his tongue is in your ear, on your throat, flat on your wrist while you still try to contain your sounds. He twists his other hand in your hair, pulling your head around to kiss you in an absolutely filthy manner, twitching inside you.

You have to break away, you're about to pass out, what with the air stolen from your lungs by his. He laughs breathlessly, drops his sweaty head against your shoulder and snaps his hips hard enough that you rock onto the tips of your toes. You'd have almost fallen but he steadies you, holds you up.

"You okay?" Mob asks, slowed and gentle again. One hand drags down, his thumb following the line of your hip. You moan hoarsely, try to twist into his grip. He fucks around, teasing, fluttering his fingers, as he huffs out a wicked, "Hey, use your words."

"F-for fuck's sake, touch me," you spit, definitely not begging. When he finally wraps his hand around you, something jagged rips up your spine like lightning. He strokes you fast enough that you almost lose it, then stops.

"Oh, you demon child, why'd you—"

"I change my mind," he murmurs. "Want you to come just from this." Then he wraps both arms around your chest in a bear-hug and starts jackhammering into you.

You can't even get your hand over your mouth properly anymore. Or on your dick. It's like he's just using you as a toy, uncaring of what you want or need. That shouldn't be hot, and yet you clench up anyway. "M-mob!" you can only cry out.

He exhales, licks the place where your spine runs into your neck. It's getting difficult to breathe with him constricting your ribcage, but he doesn't notice. His only goal is fucking you senseless. You have to admire his single-mindedness.

Mob finds a smooth rhythm and you manage to piece together one single coherent enough to wonder where he learned it, how to pull away and hold for barely a heartbeat and then slam back hard enough to shatter everything inside you.

Mob is groaning out your name over and over like just another profanity, another prayer. And the miracle comes in him hitting your prostate hard enough that you seize in his arms and wail "_Shige_" without even remembering to muffle it. You come untouched all over the door, for days, weeks.

With one more thrust, he empties inside you, rumbling deep in his chest, his mouth open and sliding wetly across your neck. His arms finally loosen and you haul in air, hyperventilating. You go limp, your muscles screaming, and you start to shake a bit from the force of it.

"Gah," you say when you're no longer so wobbly, "h'w long we been in here, security might come get us."

"Five minutes," Mob mumbles, nosing your hair, his chest rising and falling too quickly against your back. He's still half-hard, damn his youth and his esper stamina. You whimper when he gives another twitch inside you.

"Gah," you say again, "pull out slow so we don't—ack. I already defiled the door."

Mob's powers flare, energy like a wave of static over your skin as he scrapes your mess and drops it promptly into the toilet bowl. "That is convenient but so weird," you half-laugh, half-groan. "Don't do that to me, though, I'll clean up the old-fashioned way."

Mob starts pulling out, and you try to bite your lip and bear the toe-curling drag of it. Then something cool and slick pokes your ass cheek, and you twist around in alarm as Mob takes the plug and starts shoving it right back in.

You're not given time to protest, gasping and squealing as your sensitive, sore hole once again accommodates something so big. "Y-you." You try to remember syntax. "You. What the hell. Your cum's still inside me, brat."

Mob ducks his head, and you feel him grinning on your shoulder blade, through the material of your shirt. "Right where it belongs," he coos, and good gods almighty you are far too old to be this kinky but your poor cock actually jumps like it thinks it can go again. You try to stymie this by turning around to glare at him, but he's mid-stretch, pull of muscles under his arms, a peek of his abdomen under the hem of his shirt, and once again your protests die in your throat.

You emerge from the bathroom after Mob slowly, nervous about being spotted, but it's rush hour now and everyone's minding their own business. Mob adjusts his backpack and looks back to deliver the sweetest smile like he didn't just fuck you within an inch of your life and repurpose a buttplug. "C'mon, old man," he says, and holds a hand out.

He's insufferable, worse than you were at his age. You can feel bruises from being mandhandled rising under your clothes.

"Why do I love you," you pretend to grouse as you take his hand. The following smile that Mob makes is brighter and more genuine than any precious gem, as if what you said was somehow a better birthday gift than everything else.


End file.
